7. Electrochemistry

Why do electrodes get their names ‘anode’ and ‘cathode’ in a galvanic cell?

In a galvanic cell, the anode is where oxidation occurs and electrons are released. The cathode is where reduction takes place, and electrons are accepted. The names are derived from the Greek words “ana” (up) and “kathodos” (down), referring to the flow of current and electrons in the cell. Related Questions: Choose Arrhenius acids from … Read more

Where do the electrons flow from the Zn electrode in Daniel’s cell?

In Daniel’s cell, electrons flow from the zinc electrode (the anode) through an external circuit to the copper electrode (the cathode). The zinc undergoes oxidation, releasing electrons which flow to the copper electrode. Related Questions: Choose Arrhenius acids from the following compounds: HF, NH₃, H₂SO₄, SO₂, H₂S, H₂O Which salt is formed when HCl reacts … Read more

Why does the anode carry a negative charge in a galvanic cell but a positive charge in an electrolytic cell? Justify with comments.

In a galvanic cell, the anode is the site of oxidation, where electrons are released. Since electrons are negative, the anode becomes negative as electrons are given off. In an electrolytic cell, the anode is the site where oxidation also occurs, but because the cell is powered externally, the anode is made positive to attract … Read more

How can you prove with an example that conversion of an ion to an atom is an oxidation process?

The conversion of an ion to an atom is typically a reduction process, as it involves gaining electrons. However, oxidation generally refers to the loss of electrons. For example, the conversion of Cu2+\text{Cu}^{2+}Cu2+ to Cu0\text{Cu}^0Cu0 by reduction involves the gain of electrons, not oxidation. To demonstrate oxidation, we would show an ion losing electrons. Related … Read more

How can you explain that the following reaction is oxidation in terms of increase of oxidation number?

Al3++3e−→Al0 In this reaction, the oxidation state of aluminum decreases from +3 in Al3 to 0 in metallic aluminum (Al0). Since the oxidation number decreases, this is a reduction reaction, not oxidation. However, oxidation in terms of increasing oxidation number typically occurs when electrons are lost. This specific reaction is an example of reduction. Related Questions: … Read more

Why is steel plated with nickel before the electroplating of chromium?

Nickel plating is done before chromium plating to provide a smooth, uniform surface, and to improve the adhesion of chromium. Nickel also provides additional corrosion resistance, ensuring better durability of the final chromium-plated object. Related Questions: Choose Arrhenius acids from the following compounds: HF, NH₃, H₂SO₄, SO₂, H₂S, H₂O Which salt is formed when HCl … Read more

Differentiate between strong and weak electrolytes.

A strong electrolyte completely dissociates into ions when dissolved in water, such as sodium chloride (NaCl), which dissociates into Na⁺ and Cl⁻ ions. A weak electrolyte only partially dissociates into ions, like acetic acid (CH₃COOH), which remains mostly in molecular form. Related Questions: Choose Arrhenius acids from the following compounds: HF, NH₃, H₂SO₄, SO₂, H₂S, … Read more

Differentiate between oxidizing and reducing agents.

An oxidizing agent is a substance that accepts electrons and gets reduced in the process. A reducing agent, in contrast, donates electrons and gets oxidized. For example, oxygen is an oxidizing agent because it accepts electrons, and hydrogen is a reducing agent because it donates electrons. Related Questions: Choose Arrhenius acids from the following compounds: … Read more